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CPC Main Group
C01B 21/00

Nitrogen; Compounds thereof

6 direct subcodes

Child Classifications

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  • C01B 21/02 Preparation of nitrogen (by decomposition of ammonia C01B3/047)
  • C01B 21/08 Hydrazoic acid; Azides; Halogen azides

Top Applicants

Top 10 applicants by patent filingsfor class C01, 2013–2023, worldwide · Source: EPO PATSTAT

  1. CHINESE ACADEMY OF SCIENCES 4,293
  2. LG CHEM KR 3,317
  3. BASF (BADISCHE ANILIN & SODA FABRIK) DE 2,219
  4. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 2,154
  5. OMYA INTERNATIONAL CH 1,524
  6. PANASONIC INTELLECTUAL PROPERTY JP 1,362
  7. SAUDI ARABIAN OIL COMPANY SA 1,298
  8. SUMITOMO METAL MINING COMPANY JP 1,286
  9. CENTRAL SOUTH UNIVERSITY 1,243
  10. L'AIR LIQUIDE SOCIETE ANONYME POUR L'ETUDE ET L'EXPLOITATION DES PROCEDES GEORGES CLAUDE FR 1,238